As guardians of the genome, RecQ helicases preserve our genetic coding and therefore protect our cells against aging. Likewise, Nuclear Pore Complexes (NPCs) maintain proper nuclear functionality through the transport of protein and mRNA. We hypothesize, from our preliminary work, that there exists a connection between RecQ helicases and specific proteins in the NPC that function together in maintenance of genomic longevity. Our goal is to gather quantitative data through targeted proteomics to prove this interdependence. Application of these methods will identify important RecQ helicases and Nups. We propose 1) to further test a panel of RecQ helicase knockout DT40 cells and mutant RecQ helicase fibroblasts for Nup protein and mRNA levels, 2) to analyze changes in nuclear transport by monitoring energy gradients and transport of NLS-GFP, 3) to obtain accurate measurements of NPC stoichiometry through targeted proteomics.